This research proposes to create a custom wearable device that aids physical distancing by alerting the user when another similar device ventures too close. By warning people of potential safe-distance violations, this research aims at preventing the transmission of COVID-19 and reducing the risk of exposure at public places including grocery stores, pharmacies, hospitals, warehouses, and mitigating public health concerns. The proposed device can be attached to clothing, be worn as an arm-band, or clamp to common objects, such as shopping carts, baskets, and luggage. Using wireless distance measurement technology, the proposed device constantly measures the distance from similar nearby devices, raising alarm if another one is detected in close-range. It would remain undeterred by signal blocking from the user's body, yet ignore devices in an adjoining room or neighboring aisle, since virus transmission across such barriers is unlikely. Existing wireless distance measuring technology on smartphones is unable to make this distinction, necessitating this research. This work analyzes wireless reflections and signal strength variations improving the reliability of distance measurements, and advancing the science of wireless sensing. This research hopes to provide the tools that will enable quicker restoration of normalcy while remaining cautious and avoiding new COVID-19 waves.
This research creates a custom wearable device that determines its distance from all similar devices in the vicinity and warns users when safe distance is not maintained. The proposed device communicates using ultra-wideband (UWB) wireless signals allowing accurate distance estimation (ranging) in real-world multipath environments, which existing wireless technology on a smartphone cannot achieve. This work will have two core contributions: (i) a modified ranging protocol for peer-peer distance measurements, and (ii) an environment-sensing technique, performing a 3-way distinction between (a) direct line-of-sight measurements, (b) those across physical barriers (like walls), and (c) those affected by body-blocking of the signals. Modifications to existing ranging protocols are required since UWB distance measurements are based on multiple wireless packets exchanging precise timing information--a mechanism that can lead to severe wireless collisions when left uncoordinated. Environmental sensing is required to avoid false alarms. For example, false-positives (nuisance-alarms) may occur when two devices are close-by but separated by a wall. Contrarily, false negatives can occur when a person's own body blocks wireless signals causing erroneous distance measurements. These contributions are expected to advance knowledge in wireless sensing and multi-device ranging, while enabling safer public places through improved implementation of physical distancing, with impact even beyond COVID-19.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
